Make modules depend on the compiler's own module.map, as a proxy for the compiler...

Make modules depend on the compiler's own module.map, as a proxy for the compiler itself.

The headers in the compiler's own resource include directory are
system headers, which means we don't stat() them eagerly when loading
a module. Use module.map as a proxy for these headers and the compiler
itself. Fixes <rdar://problem/13856838>.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@186870 91177308-0d34-0410-b5e6-96231b3b80d8